The SecureMac team (http://www.securemac.com) says a new variant of the Boonana malware has been discovered. The new variant, trojan.osx.boonana.b, behaves in a very similar manner to the original malware, and is currently being distributed on multiple sites.

SecureMac has identified two more web sites that are currently hosting the new malware variant. Rather than the initial site which tricks users into running (and installing) the malware, these servers seem to be hosting update code for the malware. The infected machines contact these servers looking for updates to the malware payload. At the time of analysis (Nov. 2), these servers were live and distributing malware, says SecureMac.

In addition to the malware updates, these servers contain what appear to be keystroke logs from infected machines, including usernames and passwords. With a quick glance, Boonana may look like a variant of Koobface, which was discovered for Windows back in 2008.

However, ESET has also confirmed SecureMac’s initial analysis of Boonana as a new unique piece of malware, which doesn’t share a common code-base with the previously discovered Koobface worm. ESET’s threat analysis of Boonana can be found at ESETs blog.

Additionally, Microsoft identifies the malware as Trojan:Java/Boonana, and rates it as a severe threat for both Mac and Windows. Another security vendor has verified that the Boonana malware is capable of infecting Linux machines, and will proceed to join a botnet once installed. The malware also affects Mac OS X and Microsoft Windows.

SecureMac’s free Boonana Trojan Removal Tool can detect and remove the threat for Apple’s Mac OS X; manual removal instructions are included in SecureMac advisory. The free Boonana Trojan Horse removal tool runs on Mac OS X 10.5 and higher. Users may also run MacScan Security and Privacy software for Mac OS X to detect the Boonana Trojan Horse. MacScan runs on Mac OS X 10.2.4 or higher and includes a free 30-day trial. Existing users are encouraged to download the latest malware definitions before scanning.